AD 2004-24-03

This AD becomes effective January 3, 2005. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of January 3, 2005.

You can get the service information identified in this AD from Hamilton Sundstrand Technical Publications Department, P.O. Box 7002, Rockford, IL 61125-7002, U.S.A.

You may examine the AD docket at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA. You may examine the service information, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Roger Pesuit, Aerospace Engineer, Los Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone (562) 627-5251, fax (562) 627-5210.

The FAA proposed to amend 14 CFR part 39 with a proposed airworthiness directive (AD). The proposed AD applies to Hamilton Sundstrand Power Systems Models T-62T-46C12 and T-62T-40C14 (APS 500R) APUs with fuel filter housing assembly, P/N 4951627, 4951960, or 4952039 installed. We published the proposed AD in the Federal Register on May 7, 2004 (69 FR 25525). That action proposed to require installation of a bracket to prevent a failed bypass button from protruding beyond the internal o-ring seal.

You may examine the AD Docket (including any comments and service information), by appointment, between 8 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.

Two commenters request that for APUs Model T-62T-40C14 (APS 500R), we add EMBRAER Alert Service Bulletin (ASB) No. 145-49-A027, dated January 6, 2004, as another means of complying with the AD. We do not agree. That ASB does not contain instructions for installing the bracket, but only instructs the operator to use Hamilton Sundstrand ASB No. ASB-4504112-49-22, for installing the bracket. Because of this, we have not incorporated by reference that ASB.

One commenter requests that we reference the latest revision of Hamilton Sundstrand ASB No. ASB-4504112-49-22, which is Revision 1, dated January 5, 2004. The commenter states that the original ASB specified a gap dimension of 0.32 inch-to-0.65 inch, which is incorrect and unachievable. ASB Revision 1 corrects the gap dimension to the proper value of 0.50 inch, plus or minus 0.015 inch. Also, ASB Revision 1 increases the recommended compliance threshold from within 400 hours time-in-service (TIS) to within 500 hours TIS.

We agree that the latest ASB Revision should be referenced, which is Revision 2, dated October 4, 2004. The 500 hours TIS threshold is consistent with EMBRAER ASB No. 145-49-A027, dated January 6, 2004. ASB Revision 2 requires, as does this AD, that brackets installed using Hamilton Sundstrand ASB No. ASB-4504112-49-22, Original issue, be inspected one time for proper gap and adjusted if necessary. ASB Revision 2 also introduces as an alternative, the installation of a different part number fuel filter assembly for APU Model T-62-T-40C14, that is designed to prevent bypass button failure. We have added that alternative as optional terminating action for APU Model T-62-T-40C14.

We are allowing previous credit for brackets installed using Hamilton Sundstrand ASB No. ASB-4504112-49-22, Original, dated December 2, 2003, or Revision 1, dated January 5, 2004, before the effective date of this AD. We have incorporated the changes described previously in this AD.

We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

There are about 552 Hamilton Sundstrand APUs of the affected design in the worldwide fleet. We estimate that 448 APUs installed on airplanes of U.S. registry will be affected by this AD. We also estimate that it would take about 1 work hour per APU to perform the actions, and that the average labor rate is $65 per work hour. Required parts will cost about $517 per APU. The manufacturer indicated that they might provide the parts at no cost. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $260,736.

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866;

(2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

We prepared a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2003-NE-61-AD” in your request.

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):